Fluorine-containing rubbers are used in the fields of various industries such as automobile industry because of excellent heat resistance and chemical resistance thereof. Fluorine-containing rubbers are classified into perfluoro fluorine-containing rubbers and nonperfluoro fluorine-containing rubbers, and vinylidene fluoride (VdF) type fluorine-containing rubbers and TFE/olefin type fluorine-containing rubbers are used mostly as nonperfluoro fluorine-containing rubbers.
Among these, TFE/Pr type elastomers are known as a TFE/olefin type fluorine-containing rubber, and are used as a sealing material for oil in the fields of automobile and industrial machinery because of excellent resistance especially against amines.
Crosslinking of TFE/Pr type elastomers is carried out by peroxide crosslinking (Patent Document 1) and polyol crosslinking (Patent Document 2), and the former is inferior in heat resistance of the obtained crosslinked rubber and the latter has a problem with crosslinkability and chemical resistance.
Patent Document 1: JP8-295776A
Patent Document 2: JP1-299860A